The Deal
by mabel-but-slytherin
Summary: Dipper had thought that he was done with the supernatural, that he was done with the deal. But little does he know that the mysteries he once hunted are now hunting him. Spoilers through Sock Opera
1. Chapter 1

**AN: Hey! Just wanted to pop in quick to dedicate this story to an awesome user on this site, sapphireswimming, to celebrate her 100th fanfic! This story is based upon her lovely 100th fic, "Down the Road" in the SuperPhantom crossover category.**

**A quick point about this story. It doesn't feature any of the characters from Supernatural but I put it here in the crossovers section because the lore and references are clearly from the show (also "Down the Road" is a SPN crossover) as well as because I tried to write the boys in and wish they were there.**

**Enjoy!**

The first time Dipper opened the journal after leaving Gravity Falls was when he heard the barking.

* * *

In the nine and a half years since that fateful summer in Gravity Falls, neither of the Pines twins had encountered anything remotely supernatural. That didn't mean they hadn't looked: at first it was to see if any of the incredible things they had encountered that summer existed outside Gravity Falls, then it was to pass the time while they waited to go return to the Mystery Shack in June. The next summer, when they realized that Grunkle Stan refused to invite them back, citing some con of an excuse that clearly translated to Dipper and Mabel as "_it's too dangerous for you here"_, the twins dove headfirst into the treasure trove of supernatural lore on the internet, trying to find something, _anything_, that could prove to Grunkle Stan that they were more than ready to handle what Gravity Falls had in store.

But the more they searched, using their own personal experience to weed out the fantasy from the truth, the darker the lore became. It was after reading three accounts of young girls vanishing into a forest in Maryland after claiming that their short, beardy, but otherwise normal boyfriends, were actually gnomes that Mabel first went into Sweater Town. Over and over the twins would read tales similar to theirs, involving ghosts, vampires, zombies, even pixies like the one Soos accidently swatted against the Shack window, killing innocent young children to the most paranoid veterans of war.

One night in the middle of winter Mabel decided she couldn't take it anymore, that she would rather talk to Grenda and Candy on the phone instead of seeing them in person if it meant not having to deal with the creatures that haunted Gravity Falls. Mabel had hoped that her little (if only by five minutes) brother would quit, but Dipper remained as obsessed as ever, often working late into the night on his laptop looking up encounters with various creatures and how to kill them.

One time he even went so far as to ask their parents at the dinner table if they could drive down to Jericho to investigate a murder mystery. Their parents, having heard tales of Dipper trying to find who cut the head off of wax Stan and thinking it was just some touristy mystery dinner show, laughed and told him that the fourteen hour drive to Jericho was too far and he would have to wait until he was older solve actual murders. They were proud their son had such drive to become a detective, but when Mabel saw the corkboard filled with newspaper clippings of various murders Dipper claimed to be caused by a "Woman in White", she knew her brother was going down the path Grunkle Stan tried to steer them off of.

The last time Dipper even thought about the supernatural was that evening when he looked up from his latest breakthrough in his research on the true nature of werewolves – maybe he should send this to Soos to deal with the mailman – only to see Mabel curled up on her bed across the room (they had never shared a room until their summer in Gravity Falls, but one part of that summer that would never end were the nightly sleepovers), her eyes watching him forlornly, her legs curled up in an upright fetal position and tucked inside the fuzzy shield of her sweater. Dipper sighed and closed the laptop, not even bothering to save his files before pattering across the shag carpet and jumping up on the bed next to his sister.

"Come on Mabel, there's no need to hide out in Sweater Town. What's wrong?" A series of marbled grunts came out of the sweater until Mabel paused and with a jerk popped her lips above the turtleneck of her purple sweater, the one with the shooting star on it, propping her head in a way that gave Dipper the impression she very much would like to keep her head buried in the sweater if she was able to talk around it.

"I don't like it when you stay up all night looking at that supernatural stuff, bro-bro." Dipper looked over at his sister in shock. He thought at first that something went wrong with Grenda and Candy, or maybe that she broke up with yet another boyfriend at school, but he never imagined that Mabel would wind up in Sweater Town over him. "You haven't gotten any sleep this week, you haven't talked to me about something that isn't a monster in three days, and you're starting to remind me of the time with the laptop and Bill and the sock puppets and you're not Bipper but I want my brosef back!"

The last punch knocked Dipper into silence, figuratively and literally. Mabel had unwound her arms from within her sweater and punched at him, the purple yarn-clad fist hitting him in the side and pushing him against the wall. It wasn't that Mabel intended to hurt him, though the glittery girl always packed more of a punch than most would expect, it was that Dipper just remembered that he hadn't been eating or sleeping and what should've been just a hard tap actually started to hurt. As he leaned back in to hug Mabel he remembered how much this was like the fateful car ride back from the puppet show, and realized that yet again his obsession with the paranormal almost cost him his sister.

"I'm sorry Mabel, I guess you're right. I do have a tendency to get in over my head when it comes with the mystery stuff," Dipper tried to laugh the statement off, but his awkward chuckles died down at a deadpan glare from his fluff pile of a twin. "I'll try not to go out looking for anything dangerous… honestly this time, not like when we were trying to get Grunkle Stan off our backs!" He corrected himself quickly there, and sighed in relief when he saw the hands Mabel had been raising into her "skepticles" position slowly lower back into the sweater.

"Besides, anything we do we do together, right Mystery Twin?" At this he finally saw a smile growing on his sister's face, her right hand finally popping out of the end of her sleeve in order to pound the fist he left waiting in the air.

"Mystery Twins." She smiled. Then paused. "Wait, how do I know you won't just start doing more research when I'm sleeping?"

Dipper's face lifted into that sheepish grin she always laughed at, the one he usually only made if he was caught thinking about Wendy at an inappropriate time, before settling back into a comically serious look as he made up his mind. "I promise, no more looking into any supernatural. If we go on anymore paranormal adventures, the mysteries will have to find us. I won't go sticking my nose too far in if it makes you unhappy." He pulled his fist, still resting against hers, back an inch an opened it into a hand. "Deal?" The sheepish look was back, before he tried to pull his face into one of the crazy expressions Bill made when running around in his body. To Mabel, Dipper just looked like he was constipated.

"Deal!" She laughed as her hand reached forward to shake his, bouncing up and down twice to seal the promise. They both had enough respect for what had happened that day that she knew Dipper wouldn't go back on his word; that was one of the things that separated that monstrous triangle from her brother.

They both smiled for a second as they met each other's eyes, Sweater Town all but forgotten, until Mabel broke the moment by lunging forward screaming, "BODY SPASMS!" and tickling Dipper until his screams caused their parents to yell up asking the twins to be quiet.

* * *

Dipper had kept his bargain with Mabel until he was twenty two, curled up on his bed in his apartment, staring at the journal on his lap with wide eyes as the howls only he could hear continued to rage on in the background. That promise was one of the most precious things shared in a long line of secrets and inside jokes that kept the Mystery Twins closer than most others could comprehend, each having given up their chances at the best colleges and art schools in the country to go to college together at a school where they could each follow their passions, then moving into a shared apartment after graduation so Dipper could find work as a PI while Mabel sold her artwork online. Life was going great free from the supernatural and paranoia that followed that journal and everything from Gravity Falls, and Dipper didn't want to cast Mabel aside and dive back into the world of the unknown but he couldn't live ignoring the puffs of breath being blown in his ears or the chills crawling down his spine and he knew the fastest way to get to the truth would be to consult the author.

A strong gust of wind blew through what Dipper could have sworn had been a _closed window_ and pushed the cover open in front of him, seemingly taunting him with the possibility of answers before settling on a page that Dipper knew all too well. Although he no longer had every page of the book memorized Dipper knew he would never forget the letters and symbols drawn out on that page in red blood (how had he once not noticed what that was) and black ink. The three sided body and singular eye of Bill Cipher – _Demon!_ – stared unblinkingly up at Dipper before he slammed the cursed book closed, the thud of the cover slamming on the paged accentuated with a loud bark from just outside the apartment that made Dipper jump in his place.

He gazed hopelessly down at the book in front of him, his mind reasoning that he had already broken his promise to Mabel, albeit unintentionally, and there was no way he could hope to apologize without getting her involved, and hadn't his promise been that the mystery would have to find him, and it certainly already had – before he realized that he just had to damn himself and opened up the cover one final time. His hands shook as they frantically turned through the pages, his eyes trying to read or recall anything that could do with dogs, barking, monsters that only their victim could hear because he knew that if he didn't do anything fast they were going to come for him before they all too quickly found the end of the notebook and started turning the other way again.

Dipper vainly tried to remember if there was anything related to dogs hidden in the Author's notes only visible with blacklight, but Dipper cursed and panicked even more as he realized that the blacklight he had was back in Piedmont because why would he ever need one if he was done with mysteries, he only brought the journal out of sentiment. He hadn't even realized his hands had stopped moving when he looked down and saw the journal open to the one, all too familiar page that he _never wanted to see again_. But this time it looked different, and Dipper found himself unable to even register the growling that was growing louder and closer as the drops of blood splattered on the page began to bleed anew, seeping and trailing on the page into perfectly detailed drawings of an arm with forks in it, a wedding cake with a dead bride in a pink sweater on top, and Wendy, with her long, blood-red hair flowing seamlessly into the trail of blood left by an axe in Dipper's hand, the shapeshifter howling triumphantly before escaping out into the real world.

Dipper blinked subconsciously as his eyes began to blur from half-formed tears, the terrifying images thankfully vanishing as his eyes searched the page anew. His hands clawed at the text, leaving tears at the edge of the paper, until a single teardrop fell from his eye and landed on the black shape in the middle, bolded at the center of the page, and soaked right through Bill's right hand. The figure remained unchanged but Dipper's breath sped up again, his heart skipping a beat as it moved back into overtime, as from the edge of the new stain a blue flame appeared to engulf Bill's hand before Dipper's very eyes.

The static inside Dipper's mind seemed to escape into reality as he dropped the journal and screamed, pushing himself back into the wall as the howls rose to the forefront of his thoughts. He might have been in Dipper's imagination, but he could have sworn that the tan walls of his apartment were drained of all color, yet as the T.V. set that Dipper _knew_ was off just a minute ago changed from static to the eleven o clock news, everything seemed to be in perfect color. Shandra Jimenez seemed to be as stoic as usual as she announced the top story, psychic and child star Gideon Gleeful found dead in his home, his body torn to shreds by what the medical examiners disbelievingly noted appeared to be a pack of wild dogs, the cameras showing the gruesome crime scene, void of a body but filled with far too much blood and a battered journal laying on the floor, its spine bent at an unnatural angle, appearing to be the only thing left that wasn't newly painted red. For just a split second before the T.V. flickered off Dipper could've sworn he saw the book consumed by the same blue fire that had burned the page in Journal Three, that signified Bill, that signified the deal that Dipper made with the devil and the deal that Dipper broke with his sister and the life that Dipper got too deep into despite everyone's best intentions, and Dipper didn't have to be psychic to know that he wasn't getting out alive, that no one who got burned by that fire and dragged into the life ever did.

And despite the barks and howls screaming in Dipper's ears and out of his own throat the mystery hunter was able to clearly make out the demon's taunting words.

"_Tick-tock kid."_


	2. Chapter 2

**I would apologize about this taking so long to write, as I decided that I wanted to continue this story over a month ago after being inspired by some of the awesome feedback I got from this story, but seeing as I guess I haven't ever posted that I was continuing: here you go!**

**We finally do get to have the Winchesters come into play, mainly because I was depressed that they weren't, and we'll see how much closer we get to a happy ending (not yet, there's still more coming).**

**Enjoy!**

Sam and Dean pulled in to the center of campus in another one of their silent spats. It had been a long drive to Wisconsin from that small town in backwater Oregon, and the two brothers spent absolutely none of that time airing out the problems standing between them, from Dean's stoicism about his year in purgatory to the demon trials Kevin promised would seal the gates of Hell. Sam had been trying to convince Dean of a different locale to hunt a hellhound, such as the family in Idaho who mysteriously struck oil ten years ago, but Dean wasn't having any of it.

All it took was one pop-in appearance from Castiel sensing that the hellhound who ripped child-psychic Gideon Gleeful to shreds was apparently on the move towards a college campus in Wisconsin to convince Dean that the first trial would be completed here. Sam had multiple issues with the idea, and he had made his opinion that the latest victim would likely be in Hell before the brothers arrived very clear. Given Dean's lack of response, Sam smartly turned up the radio before voicing his doubts about Castiel's intentions.

But if there was one thing the Winchester brothers were good at it was working well together despite a personal dispute. Knowing it was much harder to investigate a hunt before the monster had actually struck, the men forewent their usual police/FBI getup in exchange for being two separate reporters: Sam looking for a story about any odd coincidences going on as inspiration for a writing assignment and Dean asking about any particularly gifted students on campus to feature in the school newspaper. It seemed that for once the higher powers were smiling upon the brothers: not only was the state school large enough that none of the students were suspicious of someone their age still attending and participating in extra-curriculars, but no one they interviewed was actually involved in the school's writing programs.

After listening to dozens of college students either brag or complain about their friend's athletic prowess, creative ability, or infallible GPAs (many of the "best" college students attended far more-competitive schools than this one, and while some of the kid's achievements were great, none were really worth selling ones soul over), Sam finally called Dean in frustration. Hearing that his brother had as little success as he did, the two decided to switch to a new tactic and pool their resources.

There were a few names that both brothers had recorded being brought up in at least one conversation, generally multiple retellings of the same unbelievable story as both sheer talent or an act of God, but it was clear to the Winchesters that in order to get anything out of their interviews they would have to bring something to the table. They decided to start asking about specific names.

The name Mabel Pines caught on like wildfire.

At first, not many people recognized the name, but the eyes of those who did seemed to light up when Dean asked about talent, and Sam could barely finish his spiel about looking for unusual activity before whoever he was speaking to simply burst out laughing. Then, as the boys each made their way over towards the art department (Dean was practically dragged along by a freshman fashion design major who was so infatuated with his TA that he didn't seem to realize that Dean Winchester wasn't interested in a twenty minute rant about how fabulously she pulled off sparkles on sweaters) they discovered that each and every person they spoke to had nothing but the highest regards of the recent grad.

In the time Dean spent waiting for Sam to arrive he learned that Mabel Pines and her twin brother (though people only seemed aware of his existence in that he was very clearly dear to his sister) both graduated in the spring, only for Mabel to get a job as a TA with one of the professors in exchange for getting to use the studio in creating her own work to sell online. After being shown a couple of her pieces by eager fans, Dean had to admire the obvious craftsmanship, even if the results were a bit… quirky.

How one was able to carve a perfect smiley face onto each individual piece of glitter Dean would never know.

"But what's even stranger is how much everyone seems to like her. It's creepy. I mean she's a damn TA for crying out loud. Everyone hates TAs!"

Sam hadn't even reached Dean and he was already exuding the bitchface. "You never even went to college."

"I've seen some movies. Done a couple hunts on campuses." Dean remarked as they entered the empty main hallway of the building (most of the students they were interviewing cleared out as the next classes began). "Heard a few girls complain about a TA or two. Some girls like to vent their frustration when-"

"Did not need to think about that." Sam all-too-quickly cut his brother off. For a second it was almost as if they were back to the last time they had a hunt on a college campus, back when they were travelling the country looking for John. A ghost who called itself the Hookman if Sam remembered correctly.

"Still hate it when this stuff hits campuses and preys on naïve kids." Dean muttered, apparently thinking along the same lines.

"Whoever it is this thing's after made a deal with a demon. They can't be all that innocent." Sam couldn't help but counter.

Of course given the university setting as soon as they hit the road Sam immediately looked up if there were any professors in the history or religion departments who had sudden bouts of fortune ten years ago, but it seemed that across the entire university there wasn't a single staff member who made the news in that timeframe. Whoever the hellhounds were after was probably a student.

Dean stopped moving for a second as he looked at Sam, making eye contact in a way that told Sam that this was another one of those conversations that suddenly became about him. "Whoever it is who made this deal was ten years younger than they are now when they made it. It's probably another case like Bela: they didn't know what they were getting into."

Sam couldn't help the smirk that came to his face. "Bela isn't really the best example of innocence."

"Shut up, Bitch."

"Jerk." And despite the odd direction that their day had taken, Sam couldn't help but be grateful to Castiel for sending them in a direction that brought the two brothers back together.

* * *

The brothers each couldn't help but pause outside of the door of the now infamous Mabel Pine's studio.

They would never admit it to anyone – not even each other – but each Winchester couldn't help but be a little afraid of whatever monster lie behind that door. The humans always were the freaky ones.

Looking over at each other and silently piecing their cover together, the Winchesters quickly nodded before foregoing knocking and simply pushing the door open.

For the first two seconds the Winchesters looked in it appeared to be a normal –albeit largely empty- art classroom. There were various types of painted artwork hanging from drying lines hung across the space, each with a growing range of quirkiness highly correlated to the amount of glitter on it. Sam Winchester had to tear his eyes away from what appeared to be a caricature of a cat who looked like Larry King to complete the hunter's scan of the room John Winchester had ingrained in him since birth. Seeing nothing that could potentially be hiding a person or a weapon (with the exception of a large tub that apparently held 'industrial-grade sprinkles') the younger Winchester moved on to examine the room's sole occupant.

The young woman appeared to be in her early twenties, with brown curly hair that reached down to the small of her back and covered what appeared to be a bright pink, short sleeved wool sweater. Her face bore a look of innocence and total concentration, perfectly characterized by the tongue sticking out of the corner of her mouth and resting on her lips as she chiseled the statue before her: a life-sized star wearing what appeared to be a pair of sunglasses.

Sam felt Dean lean over closer to him. "Is that Shimmery Twinkleheart?"

"…"

"What?" Dean whispered even softer. "Daytime television, dude."

Apparently his whispers hadn't been enough to hide himself from the young artist, who immediately perked up as she began frantically putting her tools aside. "Oh My Gosh you're a fan of Shimmery Twinkleheart too! I've loved that show so much ever since I -!" Only as the woman turned around did she see who exactly was at the door and her voice cut off as she took in the Winchester's well-worn plaid outfits. "You are not what I expected, but if this is the new face of Believe in Yourself then I _believe_!"

"… Are you umm... you wouldn't happen to be Ms. Pines by any chance?" There wasn't much that could suddenly throw Sam Winchester through a loop after all he's encountered, but not even the lore was enough to prepare him for this.

"Yeah! I mean, everyone always calls me Mabel. But _you_ can call me anything you'd like!"

The Winchesters shared another glance with each other, trying to find a way to normally begin an interview with the peppy young-adult in front of them. Hysteria, they were used to; concern at speaking to cops they handled all the time. Hell, the boys even knew how to deal with Becky, and her obsessiveness was _far_ creepier than the perkiness of the girl in front of them, but there was simply no natural way they could imagine talking about something like Hellhounds with someone like _this_.

"Uh, look, um… Ms. Pi-" Dean's attempt at starting a conversation paused at an expectant smile from the woman in front of them "Mabel," if anything the grin grew even _wider _and _more hopeful._ "You wouldn't happened to have witnessed anythi- _why_ are you building a life-sized statue of Shimmery Twinkleheart?!" And Sam could barely withstand the urge to smack himself in the face as Dean's gaze kept switching between Mabel Pines and the giant wax star that seemed to loom over her from its place in the back of the classroom.

The girl seemed to be honestly surprised at the question, though she didn't seemed bothered by it at all, practically bouncing on her feet as she turned behind her to subconsciously look at her work in progress. "Oh, that? Well, one of the animation students asked for my help on making stop motion figures for a student film festival and…" she paused a bit to shiver slightly before recovering with that infallible smile "given the _last_ experience I had working with stop-motion back in Gravity Falls I figured I could use some inspiration!"

She shook again as if a sudden cold draft went through the classroom just at the thought and darted back towards her station in the back. "As much as I love almost all kinds of art those people are crazy. Animation really _is_ black magic!" How the woman managed to clearly emote an exclamation point while muttering incoherently under her breath was a mystery that not even the Winchesters could explain.

"Wait. Black magic… did you say Gravity Falls?" Suddenly Sam seemed to have regained his composure as he pushed his way past Dean. The older Winchester paused for a second as he tried to remember why Sam suddenly perked at the familiar name, until he remembered seeing the former child-psychic's corpse and realized that Mabel Pines could very well be the lead they were looking for.

"Yeah! Dipper and I spent the summer there once when we were kids! It's a shame Grunkle Stan never let us come back, but I guess I can understand why he did… How did you hear of the place? It's not exactly a very large town."

Dean shot a glance at Sam that hopefully translated to 'it's probably not a good time to mention the dead kid who happens to be her age and is likely at least an acquaintance' and interrupted the conversation just in case Sam didn't get the message. He may have only known this odd girl for all of two minutes, but Dean had a strong feeling that he didn't want to make Mabel cry.

"That summer you spent down in Gravity Falls with… I'm going to guess that Dipper is your brother...?" Dean shot a quick glance at Sam just screaming 'who would name their child Dipper?' which was quickly met with a shrug that responded 'what kind of parents could have raised Mabel Pines?'

"Anyway, that summer didn't happen to be exactly ten years ago, did it?"

Something about the question, be it the inquiry into Gravity Falls or the mention of Dipper, caused a sudden shift in Mabel. It was subtle enough that the untrained eye might have missed it, but Sam and Dean had worked with enough people to notice that her posture seemed to settle down from the balls of her feet into a much stronger stance and her smile, while as sincere as always, curved into a slightly more guarded position.

"Yeah… and why are you asking?"

"It's something that we needed to know."

"And who are you two anyway? Besides being really adorable…" Mabel now had shifted into an obvious guard, her left hand grabbing a device that Sam quickly identified as a phone from a fanny pack resting on her hip. Looking into the unzipped pouch the younger Winchester could tell that there was something else in there that appeared to have the tell-tale gleam of metal, but whether or not it was a weapon Sam couldn't tell.

Dean instinctively positioned himself between Sam and the woman's guarded arms, hands raised in a gesture of surrender that made it clear that he considered protecting the girl much more of a priority than he would an average civilian, especially given the potentially-combative nature of her stance. Sam couldn't helped but be a bit shocked at the impression Mabel had made on them, and quickly realized that there was a reason they had heard such incredible things about her.

"Look, we don't want to hurt you. My name's Dean, and this is my brother Sam. We're just… concerned that there's something… strange… about to happen here…"

"And you think that something from Gravity Falls might be involved." Dean approached her slowly and calmly, obviously unsure of what the right thing to say to someone who was acting suspiciously like a hunter for someone so obviously a civilian. But if the girl had been in Gravity Falls ten years ago and her art was so obviously impacted by it…

Maybe Mabel Pines wasn't as much of a civilian as they thought after all.

Hearing no question, only acceptance in Mabel's statement Dean decided to risk continuing from his position. "We think it had to do with something that happened when you were there that summer, yes. Did you happen to meet any unusual people while you were there?"

Mabel raised an eyebrow at him for a second that seemed to scream 'have you _been_ to Gravity Falls?' which Dean took as his cue that the woman wasn't planning on bolting or calling the cops at this moment and relaxed. But once he took a second to think about it and remembered his time in Gravity Falls (both working with a combination of very persistent government agents and the _very_ tight police department and one of the more unusual meals the brothers have ever had at Greasy's Diner) Dean had to admit that yeah, that was a pretty stupid question.

The moment gave the young artist all the time she needed to catch up on the full implications of the older Winchesters questions. "Wait, you don't think that I have something to do with… whatever it is that's going to happen here? What is going to happen here? Who _are_ you people?"

Sam pushed his way back into the conversation to steer it away from any questions that might lead to any more escalation as Mabel's fist tightened on the phone she apparently forgot was in her hand while Dean took a mental note that he could cross out his suspicions of the woman being a hunter. That much pink yarn also probably destroyed any chance of stealth or bloodstain removal anyways.

"No! We're worried that whatever it is we're trying to stop is after you. Now, Mabel, have you ever heard of a hellhound before?" Dean could see in Sam's eyes that his little brother had obviously decided he was done beating around the bush with Mabel Pines and wanted to hear how much time she had left.

"No…" The word was just a weak echo of the one before it, as Mabel clearly recognized that no matter how crazy the two men seemed in front of her they were conspiracy theorists in the way Dipper was: the kind who sometimes spouted weird thing that sounded infeasible (if you could even understand them) but were right more often than not. Whatever it was that the Winchesters were chasing, whatever catastrophe from Gravity Falls had somehow decided to leave Oregon and chase her to Wisconsin was here and now and would obviously endanger her life.

With flashes of late nights watching Dipper pore over the journal in their room and of reading the newspaper clippings they found online flashing through her mind Mabel was scared to admit that she could realistically envision more monsters chasing her than she could count.

Dean could see that Sam was simply running through a script in his mind on how to best get the answer he wanted out of the girl. That Sam wasn't reading Mabel's reaction at all, noticing how all of the blood drained from her face not in guilt or even horrified recognition but in the way a child's does when told that a monster is right under their bed after they've lied down in it. Dean was even tempted to run up and grab his little brother to keep him from saying the words pouring out of his mouth.

"It's said that they work for demons, to help them collect deals." And here Dean could see the gears turning in Mabel's head, trying to latch on to the words not as someone who's had an axe hanging over them for a decade, but as someone trying vainly to see what threat lies ahead. Dean would know, he's been in both scenarios more often than he'd care for. "Ten years after a deal when the contract comes due, they show up at the person's door to drag them to Hell." Dean could hear the venom in Sam's voice, the contempt he still carried for all those who made deals with demons and got a full ten years as is due, the judgment he had for anyone who willingly through their soul away for a cause that he automatically deemed unworthy in light of their challenges. The irony wasn't lost on the elder Winchester that _they_ were ones to judge, but the accusatory nature of the statement seemed to have gone over both of the parties' heads.

Mabel Pines had finally locked on to what she needed to hear.

"_Dipper_." The word was spoken softly, as if time stood still, which for a moment to Mabel probably had. Yet the seriousness of her actions complemented that of her words as a blur of motion from the once-perky girl burst out of the classroom, shoving past the Winchesters with a blow that was comparable to that of the monsters they fought, though the girl didn't seem to notice. Even with years of physical training at the hands of John Winchester, the boys barely managed to catch her before she reached the exit of the art department in a race to her brother.

**Please drop a line and give me some thoughts, especially about the cutoff point as I was intending on having this chapter continue into the arrival at Dipper's apartment (but that would be at least another couple weeks and this chapter is already significantly longer than the first). There'll be two more chapters, and I have a couple hundred words of the next one, but we'll play by ear in terms of timing. It shouldn't be as long a wait as it was for this chapter, though.**

**Thank you so much for keeping up with this story! Whether you've been following it in hopes I would continue or just found it now, seeing that other people enjoy this story and this crossover has made me so happy to be a part of both fandoms!**


	3. Chapter 3

**Wow... was not expecting this to take so long. I sincerely apologize.**

**Good news is that I already finished Chapter 4 (the last one) LONG before I finished this one. Mainly because I had a much rougher outline of where this was going than the detailed notes I had of where it ended. But that means that I can guarantee a nicer update time for the end here, and I can finish my first multichapter! :D**

**I do have ideas for a sequel, but I'll wait until you guys can see where this is going to see how much you want it ;)**

* * *

Dean's face was hard as he pulled into the parking lot in front of the apartment complex. The ride had been dead silent the entire way from campus with the sole exception of Mabel giving directions from behind the brothers. The girl alternated between silent and frantic as if she couldn't decide on whether to quiver with fear and anticipation or remain perfectly still, although she had repeatedly made it obvious that she would have preferred to drive. Sadly the Winchesters and their ignorance of traffic laws had speed going for them, and when Mabel reluctantly admitted that her car was a ten minute walk from the classroom she was hastily shoved in the backseat of the Impala.

Speaking of the civilian, Dean made sure to lock the door as soon as he jumped out of the Impala, having easily come to a silent agreement with Sammy to lock her in the car. But as the older Winchester made his way towards the arsenal in the truck he found the backseat empty and the back passenger side door flung open from where the young woman had bolted on a direct path to the outdoor stairwell leading to her apartment before the car had even come to a complete stop.

Sam beat him to the back and had already opened the trunk and closed the back door (even in a crisis Dean had long ingrained in his brother the habit not to slam her) and was rummaging for needed supplies when Dean joined him. Due to their specific targeting of hellhounds, there was a large bag of goofer dust sitting on top of the hidden latch in the trunk (one nice benefit of the supply was that no one mistook it for a weapon, though they had to be careful in some places with it being confused for drugs). Within ten seconds the boys had procured their weapons of choice, with Dean fingering Ruby's knife in his pocket and grabbing a handgun as Sam grabbed a rifle in one hand and a long knife in the other. Subconsciously nodding at the clear implications that Sam was agreeing (or at least appearing to, given his choice of weapons) to be backup as Dean completed the first trial, Dean knocked the trunk closed and ran over to the stairs below where Mabel was unlocking the door.

The claw marks running down under the handle of the (miraculously still closed and locked) structure were an ominous sign.

"Mabel! Stay back from there!" Dean was running up the two flights of stairs two at a time, trying to crane his head to view where the young woman was furiously shoving her key in the door but shaking too much to do it efficiently.

"No! Not if Dipper's in trouble!"

"You're going to get yourself killed! The only way to ward off a hellhound is with a ring of goofer dust, and not even that-" Dean hadn't even finished his sentence, halfway up the final flight of stairs when the precious bag of goofer dust was literally pulled out of his grip. His eyes followed the soaring bag, now punctured and leaking a trail of black powder from where the metal claw dragged it along its aerial trajectory.

Dean could feel his jaw drop slightly as his eyes met the resolute stare of Mabel Pines, who didn't even wait for the military-grade grappling hook in her hand to fully contract before pushing her way through the doorframe of the apartment and entering the war zone within.

* * *

Though what lay inside was not so much a battleground as a war path. The apartment was in shambles, carpet torn and singed. But the hellhounds knew their target and had no need to stray from a deadly-straight path, leaving the artwork and casework covering nearly every inch of the walls almost unnaturally intact, although irreparably stained by ash and soot. Mabel felt her breath catch in her throat at the sight, but instinct and heart pulled her along as automatically as breathing. Dipper was in trouble and the threat lay ahead; her home, her work, and the damage both sustained weren't worth even a passing thought in comparison.

Quickly turning the corner outside the single bedroom they shared, Mabel dully noted that she was breathing heavily as her eyes searched frantically for her brother. Some reflex froze her legs in place (or at least slowed them down: the passage of time seemed more like that of a dream than reality ever since Sam and Dean brought up Dipper's danger) at the sight of the room before her. Again, there was no sight of whatever monsters had come for her twin, but that didn't mean they hadn't left their mark everywhere.

It was as if a bomb had been set off: every inch of the space had been impacted, the damage radiating outward in a sphere that reminded the girl of Gravity Falls' apocalyptic anomalies all those years ago. But it was obvious at the sight who the target was. While Mabel's bed sheets were shredded on the edges, the wood making up the frame burned with holes that mocked the eyes normally dotting the pine finish and the siblings' mutual television set was now cracked and sparking blue tendrils of electric current; Dipper's possessions were decimated: sheets, clothing, anything of his not heavy enough or well tied down was now littering the open space the twins once prided over sharing for larger projects. His blankets were no-longer in a recognizable rectangle: triangular shards sprawled among the long strips entangling anything touching the floor.

Both boy and book were caught in its snare.

Mabel hadn't seen the Journal open in nearly ten years, but not even she could forget the look of the yellowed pages and old binding that was once her brother's bible. Despite the age-old damage, the artifact was innocently sitting unblemished by the recent chaos, open to the page of the demon who got them into this mess and just out of arm's reach of the mystery hunter who it betrayed.

Then her eyes caught Dipper's form and the world (no matter how slowly it was crawling earlier) came to a dead stop. His hand was stretched loosely towards the Journal, as if at one point he had been reaching for it, but was forgotten in necessity of supporting his body weight. His ankle was tied to a shred of sheet pinned under a bedpost, his lanky-but-nearly-filled-out-with-age body appearing to be entirely ensnared despite the small but tactical point of contact. He was nearly still, having obviously frozen in the process of crawling backwards when hit with the backlash of the bond, but his lips were quivering as if on the verge of words and his eyes, stark white framed by a ring of too-dark bags and too-pasty skin, darted frantically with panic and _life_.

And where he was looking, Mabel noticed as the pounding of her heart and the gasping of her lungs lost their monopoly on her eardrums, must not have been as empty as she first thought. Because suddenly her entire core was shaken by the unison growl of dogs.

Not dogs, hellhounds. Ones getting ready to pounce.

Time returned to its proper, breakneck speed as Mabel jumped into action, literally. Reaching for the hanging fan with her bare left hand the woman leapt into the air, right arm swinging the grappling hook and its precious cargo over her shoulder and spewing dust as she went. Years of practice with the device paid off: by the time she landed with a roll behind Dipper, a thick black line had slashed onto the floor to his right, and with the masterful stroke of a painter Mabel whipped the bag in a circle on the other side, closing the odd semi-circle/triangle of thick goofer dust she made with the back wall. Hands quickly reached to pull her prone brother's shoulders back and drag him to the center of the polygon from his spot precariously close to the edge. As Mabel applied a healthy dose of goofer dust to fix the break in the warding where the sheets tying Dipper had ripped under her pull, she replayed Dean's words in her mind and ruefully hoped the mysterious stranger wasn't too picky when he specified a circle.

Mabel could hear two pairs of combat boots running their way through the apartment and remembered that the Winchesters were behind her. Calming slightly at the reassurance that she would simply have told hold down the fort until they came up with an attack strategy Mabel stepped in front of her out-of-it brother and readied the grappling hook in front of her.

Hopefully years of practice hitting everything in sight would be just as applicable to aiming at invisible targets.

* * *

Dean hated to admit it, but he was scared upon following Mabel Pines into her apartment that her body would already be strewn alongside her brother's before they had a chance to reach her.

It was a story the Winchesters had seen too many times. Anyone they got close to, even if just for a few hours, hell they hadn't even met Mabel Pines an hour ago, was liable to turn up dead before they left town. Especially cute young women. Even the weird ones.

So Dean Winchester found his jaw dropping for the second time in five minutes as he followed the ash and soot to the bedroom door. Mabel Pines huddled on the far side of the room, sheltered under a triangular window of broken glass and firing her grappling hook into the foray of hellhounds growling menacingly with one hand while holding a boy who could only be her brother close by her side with the other.

She kept sending Dipper glances and momentarily squeezing him tighter, and while the hunter first thought the gesture was the artist reassuring herself that her twin was still alive, as Dean's surveyed the situation he soon realized that wasn't the case. As the hunter checked over the boy to verify that he was indeed alive, Dean noticed the kid's eyes frantically shifting back and forth in a pattern that reminded Dean of when he Lilith sicced the hellhounds on him. Recognizing the terror and desperation, it became obvious that Dipper was already seeing the beasts.

They really had come just in the nick of time.

But then Dean heard one of the howls shift into a pained yelp, and was stunned that Mabel Pines was managing to _snipe_ the invisible hellhounds. Her gaze shifted back to her brother, then followed the direction of his glance before firing again. Mabel was using Dipper's guidance to fight them off, all while huddling in the protection the warding of goofer dust provided.

Warding that the Winchesters were not sheltered behind.

It took a few seconds for the hellhounds to notice that the boys had entered. They weren't the dogs' targets after all, but there likely wasn't a monster in Hell that wouldn't relish in the opportunity to drag the infamous hunters into the Pit. Shifting into a more overt fighting stance and holding Ruby's knife in front of him threateningly, Dean suddenly wished that he had brought something a little bigger when facing the one monsters he outright feared. Like explosives. But that thought only reminded him of Ellen and Jo, and Dean tried to shake the fear and guilt off in favor of battle. Seeing Jo's reflection in Mabel, a young hunter cradling the only family she had left, only made the emotions worse.

His thoughts were finally knocked out of him by a metal grappling hook firing right towards him. Just a few feet away from where he thought he'd have his manhood hooked Dean saw the hook grip into nothingness and come to a quick stop. A split second and a deft twist of Mabel's hand later the metal tore through the hidden flesh, red hellhound blood spilling and staining the white carpet.

Staring up into Dean's horrified expression the sniper yelled out, "Hey, watch what you're doing!" After a quick pause and another fire the girl corrected, "Actually, no, stop watching and actually _do_ something! Aren't you supposed to be the guys who take this stuff down?"

Sam let out a light chuckle as he stepped out from behind where Dean had subconsciously blocked the doorway to keep him from entering the room. Hefting up the rifle he had brought with him, Sam quickly aimed into the bedroom, away from the prone twins on the other side, and fired. Seeing the bullet leave a sizeable dent in the ground quickly told the boys he missed.

Firing out a few more shots all proved to be just about as effective. After bursting what appeared to be a sizable paper mache pig, Mabel took a second amongst her swinging of the grappling hook to shoot a glare at the taller man and shout, "Hey! Stop aiming for Waddles!"

Another swing must have hit a hellhound (the one dodging Sam's shooting as it seemed to weave its way closer to the Winchesters) in a particularly sensitive spot, as it let out a yelp and a crash as blood blossomed across the carpet. Taking in the damage unleashed by the young girl Dean let out a low whistle as he leaned over to Sam and whispered, "Hey, why don't we have one of those in the Impala?"

"Beats me." His brother shrugged, shifting the rifle's weight in his arms.

"When this whole trials thing is done, we're going to one of Bobby's old contacts and buying a couple of those. Iron. Or maybe silver…"

"Yo! Shopping spree later! Less girl talk more GRAPPLING HOOK!"

With her signature cry Mabel fired said weapon at an empty space, the weapon quickly stopping came to a dead stop in the way that usually signaled it hitting its mark. But this time it wasn't the young artist who twisted away. Instead, a low sound came from behind the hook itself as the metal seemed to move of its own accord.

Next thing they knew (or at least the three aware enough to recognize the severity of the situation knew), the hellhound was on its haunches and backing up, dragging its attacker and the prey she was holding on to towards it. More importantly, it was pulling them closer and closer to breaking the thick line of goofer dust keeping them safe.

"Dean! Sam!" The girl's panicked cries only increased the urgency in the hunters. They tried to look for openings, but the light mist of the hellhounds' panting breath revealed that there were far too many of them for the hunters to find a decent opening. And as Mabel's arms and legs were nearing the thin black line keeping her from the foray of monsters after her and her brother's blood, it was becoming more obvious that even cutting the line, or simply having the girl let go, wasn't an option. More dogs were already pawing at the goofer dust, sniffing at it and blowing it away with their hot breaths. It wouldn't be long before the twins were completely defenseless.

Mabel closed her eyes and suddenly seemed to relax despite the tension pulling her closer to Hell. Letting out a breath she squeezed her twin tighter to her side in a quick hug and loosened her grip on him. With a soft "Dipper, I'm sorry" the girl let go, pushing herself forward into the pull. Using the sudden momentum in her upper body to swing to her feet, the artist transitioned into a leap over the line of goofer dust and dove into the fray.

"MABEL!" She managed to twist herself in the air so she blew past the grapping hook still resting in one of the hellhound's mouth, her shoulder slamming into the blood-stained singed carpet beneath her and keeping her from sliding back far. Instantly she felt the grappling hook fall limp against her side, the dog dropping it in favor of pouncing on her exposed form. Another one breathed down her neck, sending a chill of terror down her spine despite its too hot, humid breath.

* * *

She could hear Sam and Dean behind her, screaming her name through the ever-present crescendo of howls, and through it all Mabel could swear that in the back of her mind she could make out the unforgettable sound of Bill's grating laughter. More than anything the jarring chuckles brought out a rage in her over everything that demon had done, everything he had taken away from them ten years ago without ever letting them know, how he had pushed them over the edge and just waited, watching until the day he could swoop in and take her brother away again. This time for good.

This time not even a hastily made sock puppet could reunite them. But she wasn't going to be a puppet in Bill's little game anymore.

From between the wide stance of the hellhound looming over her, Mabel fingered the refreshing cool of the grappling hook, dragging her hand along the metal and not even caring when she reached the edge that was warm and sticky with blood. The rope was loose from being pulled so much, and even if she could hit the switch to coil it the dog would probably kill her at the sign of sudden movement. As of now it she could sense the invisible force looming over her, as if it was playing with its food.

Or waiting for some sort of command.

But the girl knew she wouldn't be the one to give it to him, and she certainly wasn't going to wait until the thing decided that it was ready to pounce on its own. One bat of its paw would probably crush her ribcage, if not outright vivisect her with its sharp nails. Even if she struck first, incapacitated it, killed it, the one right behind her would maul her in seconds.

But at this point it wasn't about getting out alive. It was about protecting Dipper, about making as much hassle for Bill trying to kill them as possible. And if taking out one of these beasts gave the Winchesters a tiny bit more of a fighting chance, then it would be worth it.

Not like she would survive either way.

And with that morbid thought, she closed her fist around it and hooked her elbow, stabbing the metal claw right into the hound's vulnerable stomach.

Its growl turned into a scream. The sound was met by the gushing and warm spill of hot blood pouring all over her. But none of that mattered when the beast collapsed onto her pinned form, its paws batting feebly with the last moments of life, but still enough to tear into her exposed arm, and all Mabel heard were piercing screams she vaguely recognized as her own.

* * *

Neither Winchester was willing to watch the center of the fight as they dove into the battleground, covering each other's backs and hoping that gave them a hope at survival. They both knew that if they turned their eyes just a little bit towards the left they'd see Mabel Pines as clear as day, her pink woolen sweater clumping together as it soaked in her lifeblood, claw marks littering her form in a way that would make any person sick. Especially one who had watched their brother die in the very same way. Certainly one who had already undergone such torture themselves.

It wasn't like the invisible hellhounds would do anything to block the horrific view.

Between the demon-killing powers of Ruby's knife and the specially smelted bullets of Sam's rifle (melted down iron mixed with goofer dust in a desperate hope that hellhounds liked being pumped full of the stuff as much as they did when it encircled the floor), it seemed that the boys were making progress. There were a few places where dogs seemed to have collapsed, and although it nearly tripped Sam's gargantuan legs when he encountered a form Dean had felled, it was better to have a sign of progress than avoid invisible obstacles.

In another silent agreement they decided to worry about the trial later, once the threat was gone. It'd be easier to ritualistically soak in the blood of a hellhound when there was only one or two left than when a whole pack of them who were on the verge of killing both them and innocent civilians.

A quick glance to the far side of the room assured that the kid was still safe behind protection, a few hounds likely still pawing at the line, but the majority of their dwindling numbers were now focused on the hunters picking them off.

Or at least that's what Dean hoped. He couldn't bear to think of them running from Dipper merely to snack on the more vulnerable meal nearby.

Due to their delaying of the trial, neither brother was particularly trying to make the hellhounds bleed. Bullet wounds, while ranging in damage from incapacitating to deadly, were small, and Dean didn't have the time to twist his blade or drag it to deepen the cut. There were too many of them, and they were far too quick for the hunter to take his time, and the ceremonially serrated blade took effort to drag through such thick muscle.

The world faded away to the red haze of violence, and for a brief second it reminded Dean of his eternity in Hell. It was a fitting comparison, but not one the older Winchester was apt to relive.

A scream broke Dean out of his nightmare.

He had never heard Mabel scream. Thinking back he had barely known her long enough to hear her laugh beside that fake flirty one she gave off upon hearing that he knew of Shimmery Twinkleheart. But as soon as he heard the sound there was no doubt in either of the brothers' minds that it belonged to the young teacher's assistant who had quickly triggered the internal brotherly instinct that would do anything to protect extended family. The girl reminded him of Charlie, and Dean cursed that he wasn't able to give her as happy an ending as the Queen of Moondor.

He couldn't stop his instincts from turning his head to look. His eyes all too quickly took in the sight of her bloody form, long gashed running down her left arm right under the end of the short sleeve and red covering what once was a design on her handmade sweater.

Sam had been closer, and had noticed the telltale signs of another hellhound coming right behind her, getting ready to lunge for her head. Pulling the extra knife he had brought along out, knowing a rifle would be useless from this movement and range, the tall man threw himself at the oncoming dog and aimed to slice what hopefully would be its throat.

* * *

Sam could feel his shoulder hit the ground as he fell on his side, pushing himself up and holding the knife that had just slayed one hellhound out, ready to face off against any other oncoming threat. Looking to the girl next to him, then down at his blood-soaked form, Sam started to mutter an incantation under his breath.

Not much good would come out of this, but at least the first trial could be complete, and the lives lost could mean something.

* * *

Dean could feel that the battle was dying down around them. Somehow, perhaps in a stroke of good luck that went towards making up for the Winchester curse that seemed to follow them everywhere, there hadn't been another hellhound ready to pounce on Sam when he went down as there had been with Mabel. Sam was better prepared for starters, but Dean didn't know what he would do if he lost Sam again after everything they'd been through.

He suddenly remembered Dipper, still laying barely conscious on the floor behind the ring-like formation of goofer dust and shivered at the thought of when the boy would awaken alone with strangers and his sister's corpse. Neither of the twins deserved the fates that were waiting for them.

Finally having a chance to breath, Dean dared to spare another glance towards where Sam and Mabel lay on the floor. It was hard to imagine that they were only a few yards apart given everything that had gotten in-between them, but seeing straight through the invisible bodies of the hellhounds made it obvious how close-by they really were.

Then Dean felt his blood run cold again when he saw Sam's lips moving, a bloody sheet of paper procured from his pocket where he must have copied down the incantation to complete the first trial. His little brother's hands and front were covered in blood from where he killed the hellhound that had been leaping for Mabel, and Dean was frozen as he looked at himself and realized he was far too clean of blood to stop his brother and do the ritual himself.

A soft glow started up near the younger Winchester, but it seemed hazy, and Dean couldn't quite make out what it was covering. He felt himself looking back over Mabel Pines' form, lying on the floor next to Sam and looking for all the world like a sleeping princess.

Eyes far too used to checking over injured hunters and near-dead civilians for injuries scanned her form. Strangely enough, he couldn't find a cause of the most worrisome blood stain covering her chest. Where there shouldn't be a scratch or dismemberment was perfectly untouched, and Dean started praying in his head when he saw the bloody grappling hook in her hand. Her chest was still, but it could just as easily been from fighting for her life against the pressure of being crushed by the heavy corpse of the attacking hound as from already slipping into death itself.

But the prayers hoping she survived turned to curses as Sam continued the chant, and Dean realized that the small glow could just as easily be aimed towards Mabel as Sam from his angle. Sammy probably hadn't realized it either, but Mabel Pines had killed a hellhound first, and quite literally bathed in its blood…

Shit.

* * *

Mabel never knew what to believe about life after death. Even as she cut through the hellhound with her trusty grappling hook and felt its life dim in tandem with hers, she didn't experience the same "life flashing before your eyes" experience that everyone always went on about.

A part of her felt kind of cheated. After spending so much time compiling scrapbooks of her most wonderful experiences she was looking forward to seeing her subconscious replaying all of her greatest hits. There was no light at the end of the tunnel, just blood and what seemed to be a giant shadow looming over her (maybe that's what the hellhounds actually looked like?) as the world faded into black and grey (even calling it white would be optimistic). The whole "at peace" thing was also really understated: while Mabel hoped that her sacrifice would be able to buy enough time or damage for Sam, Dean, and most importantly Dipper to live, she was generally feeling pretty shitty about the whole experience.

Apparently dying a painful death made even an optimist feel pretty cynical.

But all of her metaphysical musings (which were so much more typical of Dipper, were they not? Guess it's only fair, since hopefully she would be taking Dipper's place and he could live the long and successful life she knew he would) were nothing in comparison to the physical sensations. No, her mind was fully in the moment, filled with determination and rage as she felt the blood pour over her, warm in a sticky and twisted way that she guessed was a fine metaphor for life. Then none of that seemed to matter after the crushing weight and the searing pain.

She could only hear screaming: both the hellhound's and a bit of Sam and Dean's panic, but mainly her own. She could taste the metal and sulfur that had been potent in the air ever since she started fighting, and given its potency the sense was nearly indecipherable from smell at this point. Her vision was starting to fade further and further from shadows and greys into a pure and complete black, and Mabel mourned that she would never again be rescued by Crandalf the Fabulous, Color Wizard and Savior of the Great Depression.

But a burst of color did miraculously come out of the corner of her vision just as she had turned her head to rest her weak neck and somehow wound up facing the prone form of her brother. He was still frozen in unconsciousness, and looking almost as bad as she felt, but there was the soft movement indicative of breathing in his chest. Well, that or Mabel's blurring vision was giving the illusion of such, but despite the sudden flood of cynicism she would not die believing that her little brother went first. Just as even the figure she had spent her entire life beside began to fade away, she could swear she saw a flash of blue out of the corner of her eye, but her bleary mind argued that that couldn't be right, Dipper had outgrown that Pine Tree hat years ago.

Then suddenly her brother's voice echoed in her mind and Mabel was so happy that she could hear him say goodbye one final time, happier than she had ever been in her bright, too-short burst of life, glitter, boy bands and joy.

But the voice didn't give her the goodbye she wanted. Mabel's fading thoughts seemed to play for her what she wanted to hear, sounding suspiciously like they were echoing what she needed in order to take the step and give in (though a part of them were claiming they were not her own, and introduced themselves as 'Tessa'). But before she could finally close her eyes to some semblance of peace, to her complete and utter horror, just a second before the bliss of oblivion sunk in Mabel could've sworn she heard Dipper say, "Deal."

* * *

**Again, don't worry! The next chapter is already finished and will be posted much sooner! Sometime after my birthday next week and when I feel that enough agony has passed to make the anticipation for the chapter worth how excited I am for it. This was a ton of fun to write once I got over writer's block (it came a third of the way through with me thinking I only needed a couple hundred more words and then all of this happened) but I must say the last chapter/epilogue is my favorite :)**

**Finally, I will end with a reminder that ever since the first oneshot chapter I had requests to extend the story so there could be a happier ending where the Winchesters save the day and rescue Dipper so he didn't wind up in Hell. My slogan is ask and ye shall receive, but I'll add an addendum of be careful what you wish for ;) .**


	4. Chapter 4

**AN: Posting this chapter is something of a milestone for me, for a number of reasons. First, it's the first multichapter story I've ever completed, and that's an incredible feeling. Second, I've always had a lot of love for this fic since it's what got me back into writing this past year (hard to believe it's been seven months!) and has introduced me to a whole community on tumblr (I made my secondary blog Mabel-but-Slytherin (formerly acekanigirl) to post the first chapter of this) as well as solidified an incredible friendship with the amazing sapphireswimming that the original oneshot chapter was dedicated to.**

**As if that wasn't enough, this is the first time I've written a chapter out of order, which took away _way_ more pressure writing it out than I knew I was even experiencing, and that in turn taught me a ton about how I write. Sadly even the stress I put on myself to get the next chapter up can kill my muse, and writing a chapter without that was freeing in more ways than one.**

**Having had this chapter done since March (I was originally hoping to post it on my birthday last month, but chapter 3 took until about the week before to write and RUINED EVERYTHING!) I've really been looking forward to sharing it with you all, as personally I think it's some of my best work, especially with dialogue. It's sad to say goodbye with this fic, but I have _so many plans_ for the sequel. In fact, everything since the first line of chapter two has been building up to the plot that comes after. That said, I can't give any guarantees on when the beginning of that will be except that it'll be months, and if it comes before that it'll be extremely irregular. I'd love to be the author who can write it all and update weekly and be amazing, trust me, I want to see this fic more than anyone, but the fact of the matter is that there are giant transitional gaps in what I've planned, literally multiple prequels I have to decide if I'm going to finish or scrap and how that will impact the future plot, and where the hell this odyssey will be heading once I pass into the sea of possibilities my mind dreamed up half a year ago.**

**If you would be so kind, I'd actually love to hear where you think this is going after this chapter! I've tried to weave in subtle foreshadowing for some things while leaving others entirely in the dark and I want to see how much people can pick up on. I'll try to make little prizes (requests of some kind) for anyone who either guesses close or inspires me for a smaller plot point to include. Sapphireswimming knows most of the major bumps because I bounce ideas off of her, but we haven't talked as much recently and I'm sure she can tell you I have the major drops but not all of the twists and turns.**

**Not going to leave an AN at the end because I've rambled WAY too much here, but thank you all for being incredibly kind in reviews and support here, and hope you enjoy the final installment (for now!) of _The Deal_.**

**Disclaimer: there is one line in this "Get to the point already!" "Which one? I've got three!" that came from a post on tumblr. I'd cite the OP, but it hasn't been on my dash in over four months. So if you know the url tell me and I'll update this, but if not be aware that it isn't mine.**

* * *

Dipper could feel his grip on reality beginning to fade.

It wasn't entirely like falling asleep, with the knowledge that consciousness is fading as the whole world seems to dim. It was more like falling straight into a nightmare, with certain sensations fading in and out as if some demonic child inside the mind just realized they were tall enough to reach the light switch and discovered it had a dimmer. The growls and howls would come and go, sometimes in time with the visibility of the hellhounds moving tauntingly towards him to create an unholy crescendo, sometimes flickering out of tune with his senses in a way that made the boy all too aware that these threats should be invisible.

Some sensations were all too easily able to cut through the haze, overwhelming Dipper with their presence. For instance, the all too familiar neon gold glow and carefree nasal voice made the whole world seem out of focus by comparison.

"Well, well, well somebody's looking desperate!" This time the echo of Bill's words was stronger, not a reflection of an old memory but the real thing. The demon appeared from just at the edge of Dipper's peripheral vision, laughing as he circled the adult the same way he had ten years ago when Dipper was just a twelve year old boy who stuck his nose in too deep. Dipper would've turned around to follow the demon or turned his head, anything to show that he wasn't completely helpless under that glowing stare, but despite the adrenaline and nerves coursing through his body like a static shock the boy found his tense muscles too tired to move.

"Hey, Pine Tree! Long time no see!" Bill stopped and focused before appearing to smirk at the boy for a second before continuing on. "Well, for you at least. I've been keeping an **eye** on you," his one visible eye enlarged and glowed that hellish red it did whenever the normally dapper demon mentioned it, "and I must say kid, you look like hell!" The demon came to a stop in front of Dipper as he burst out laughing. Keeling over at his own joke Bill kicked himself back to rest in the air between Dipper and the hellhounds, wiping his eye and relaxing as if he was catching up with an old friend on a lounger.

"Heh, it's funny because you're going to Hell."

"Bill! What are you doing here?" Dipper's voice came out as raspy as his throat felt raw, which was saying something because his body was already on fire in a mock foreshadowing of what was to come. He could barely hear his voice, but the demon had no trouble understanding him as he seemed to glow at the attention.

"What? I can't come enjoy the show as I watch my favorite Pine Tree burn? I even brought s'mores!" He snapped his thin black fingers and a branch the size of his arm appeared in his grasp, two marshmallows resting perfectly on the end until the demon quickly waved his hand and the gag vanished again.

"I know you. You wouldn't just go away for ten years and reappear right now unless you want something." Dipper tried to keep his voice strong despite the strain, but he couldn't help but wince at the sound. He hadn't heard his voice crack that much since, well, since he was twelve in Gravity Falls.

Bill didn't seem to react to the obvious attempt at intimidation, looking down his planar face at Dipper as he still lounged in the air above him. "I've never really gone away kid, I already said I've been watching you-"

"-and you wouldn't bother leaving the Mindscape for this unless there was something you thought you could gain. What is it?" Dipper sent the harshest glare he could to the unblinking eye staring blankly down at him, trying to move his arms against the combined force of his shock, exhaustion, and whatever power the demon was exerting.

The demon seemed frozen with a lack of expression that Dipper couldn't help but define as contemplation, before it darted out of its relaxed position and flew right in front of Dipper's face. "I wouldn't keep struggling if I were you, Pine Tree. Even if you could move, even if you could scream, there are some… spectators… here who we wouldn't want to startle with sudden movement." Dipper unconsciously found his eyes darting around Bill trying to make out the black smoky hellhounds deeper in his vision, but found reality blending into too many shades of gray to be discernable beyond the golden burst of color that was the dream demon.

They stared at each other, two human eyes meeting a single demonic one, until Bill was apparently satisfied, as he flew away to approximately where he was before, chuckling as he went. "Ah, Pine Tree, I've missed these little conversations of ours! Always so adorably serious and trying to dig straight to the bottom of things!" Even through his paralysis Dipper managed to flinch at the demon pinching his now-thinned-with-adulthood cheeks. "Oh, I'll miss it without you here, with only the reverberating sounds of your endlessly tortured screams from the Pit for entertainment." A black and white handkerchief appeared in Bill's hand as he wiped away a comically large tear from his single eye as he turned away from Dipper in an act of modesty, his single feature clearly dancing with mirth behind the faux sadness as he saw Dipper pale at the mention of his fate. "Well, not that these last ten years haven't been _boring_ without all the monster chases and heh, the pain is hilarious, but I'm sure you'll agree with me that you alive beats the alternative!

"I mean, if you're really so eager to get to the good part I can end this now and we can skip to when all of these little guys here tear into your flesh." Bill paused from where he was turned away from Dipper, clearly waiting for the boy to give him some kind of response.

It took a minute of glaring from Dipper before the former mystery hunter eventually ground out, "if you're expecting me to thank you for delaying for a few minutes the eternal damnation that _**you**_ put me in you're not going to get it."

The response seemed to be exactly what the demon wanted, for Bill seemed particularly pleased as he turned around. "But Pine Tree, that's exactly what demons do! Not to mention that you were so eager to find out all of the secrets of the universe, you made it so easy! Well, now you know that there really is such thing as Hell. And guess what, kid: you're going there!"

Dipper tried to open his mouth to make another sarcastic comment but found even that unable to move, apparently Bill had a script in mind and didn't want Dipper changing it. Sensing the attempted action, the demon, literally glowing in anticipation, floating back over to his prey. "But I wouldn't be lying if I said I didn't have some regrets over dooming one of my favorite humans. I mean, I haven't been able to get a good night's sleep ever since we sealed the deal!" The laugh at his own joke was briefer this time as Bill quickly returned to his point, "and that's why I decided Pine Tree, you're much more entertaining to me alive then dead. I mean, never-ending torture on the rack gets kind of repetitive."

Dipper felt his heart instinctively flutter at the glimmer of hope. "What are you getting at Bill?"

Bill floated down in front of Dipper and held out his hand, suddenly burning with that blue fire that Dipper had been hallucinating in the corners of his vision ever since the howls started. "I'm willing to call all of this off and let you go back to being the lovably insufferable Pine Tree, all you have to do is make a deal!"

"You're crazy if you think I'll make another deal with you after you stole my body!"

"Shhh, kid, let's keep this between the two of us for now, if you know what I mean." The demon glanced back at the hellhounds again before turning to Dipper, his eye narrowing. "Here's the thing, Pine Tree. I'm just in sales. As soon as I make a deal, the contract's literally out of my hands. If I could give your soul back, I would. But there's red tape and all that jazz, not really my color if you know what I mean. So I went to the big boss and made him an offer he couldn't resist. You agree to the same deal he did, you go free."

Dipper scowled as he tried to figure out what kind of deal Bill was getting at. If there was another player involved, that could mean that Bill had rules he had to follow, rules Dipper could take advantage of. But on the other hand, a higher demon could be even more unpredictable than Bill, and that was a scary thought. Then again, if there was one thing Dipper knew about demon deals it was that you could never get the upper hand, and that was exactly what Hell wanted.

Still, it wasn't like Dipper could move away right now, and he was already jumping out of the fire and into the frying pan, literally. "What kind of deal are you looking for? Because if you think I'm letting whoever your boss is run around in my body, you're wrong."

Whatever he said apparently amused Bill, because the demon let out a bark of laughter which was quickly echoed by the hellhounds behind him, making Dipper jump in his skin. "Ah, don't worry so much Pine Tree, Crowley's already got another vessel that's much more _tailored_ for him, if I would say so myself. Heh, I'm actually pretty proud of the deal I got lined up for you, kid, you even get to keep your soul for more than ten years this time. Apparently the sacrifice your immortal soul is a one per customer kind of fee, who would've guessed! You even get to keep possession of your body, well, most of it. All I need is an eye!"

"…My eye?" Seeing the odd expression on Dipper's face made Bill laugh again as he probed against the boy's open mind.

"Yeesh, kid, not in _that_ sense! Though I must admit, depth perception would be deluxe. No, all I want to do is borrow it! You get to keep it in your head and everything!"

"Bill, just get to the point already!"

"Which one? I've got three!" And suddenly Bill had his signature cane out and was doing jazz hands… "But seriously kid, if you're that eager to get to the point, there's even more of them on those hellhounds' teeth!"

Then the humor switched off as suddenly as Dipper's blissful break from the howling as he was forcibly reminded that Bill literally had his soul in his hands. "You see, Pine Tree, despite being an all-powerful being of pure energy with no weaknesses, there are some things that even my one eye can't get a good look at. Powerful warding and spells to hide things away, kind of like in that journal." Seeing the sudden longing gaze Dipper was directing towards the journal sitting innocently out of reach Bill couldn't help but laugh. "Not that that ever helps once you make a deal!

"But man, how lucky am I that no one ever bothered to create wards against weak little noodle-armed humans! You see, all you have to do is help me with a couple of humans who've managed to get far enough on Crowley's bad side enough that just their location is worth more than your soul!"

"You really think I'm going to help you out after everything you've done to me? For all I know you're just going to find these people and kill them then drag me to Hell when you're done!"

Bill didn't seem phased by the having Dipper shove the loophole in his face, if anything (from what frustratingly little Dipper could read of that two-dimensional expression) the demon looked proud. "Aww, little Pine Tree picked up on the trick first thing off the bat. They grow up so fast! But don't worry kid, you got your good old pal Bill Cipher looking out for you! You see, if this was as simple as trying to track down the Winchesters, we'd be done right now! Because they're right here!"

Suddenly the yellow triangle backed away from where he was floating in front of Dipper's face, truly clearing the boy's vision for the first time since the demon started making his proposition. Blinking away the glowing spots in his vision (though after a few seconds of trying he belatedly realized that some of the swimming black blurs were actually hellhounds), the young hunter realized that he, Bill, and the hellhounds were no longer alone. Standing out in bursts of color as other minds do in the Dreamscape, sharing in the fantasy or not, were two men who for a second Dipper overlooked as human, really, who in their right mind wore _that _much plaid?

They also paled (in more ways than one) in comparison with the star of pink fuzz, brown hair, and red… blood… that was Mabel.

Dipper's eyes roved over his sister, frantically looking for any signs of injury that could've resulted in her bloodied form, not finding any on a first glance, then checking again and again until a voice in the back of his head hopefully pointed out that it might not be hers. Sure she was fighting, and she was strong, but she was his sister putting herself in danger for him and Dipper suddenly felt a ripple of fear that shook his whole body more than the thought of his own death ever had.

Because even if Mabel was not the one shedding blood, from the angle of the dark shape looming over her, and another one moving behind in her blind spot (everything was her blind spot because she wasn't meant to see them because she wasn't meant to get involved) Dipper could tell that soon Mabel would not be the one coming out on top.

All too quickly he could feel his vision being torn from his sister against his will, his eyes slowly rolling in his head as Bill forcibly dragged his vision away from Mabel and onto the intruders the demon wanted Dipper to see. The Winchesters, the part of Dipper that had been trained by years of study to remember the little names and details that could potential help solve a mystery piped up, but why would they matter so much…?

Until a glance at the shorter one's face sparked a burst of recognition and another blast of fear.

Sam and Dean Winchester. Mass murderers. Satanically obsessed. Had a penchant for young women, or at least the older one did, and a miraculous ability to somehow fake their own deaths. Most importantly, they were standing right behind Mabel with a sawn-off shotgun and one of the largest knives Dipper had ever seen glinting a reflection of grayscale and golden glow.

"Come on, kid. Your soul, free as a bird, and all you have to do is keep an eagle eye on two criminals who need to be watched. I thought this was what you wanted to do with your life! You don't even have to stay close to them, just track them from a distance and put those detective skills of yours to use." Dipper couldn't turn his head to see Bill resting above his shoulder, couldn't tear his eyes away from the blurry face of the murderer standing before his sister. Could barely make out anything other than the bloodlust on his clearly emotive face. For the first time since any of this began Dipper felt cold, a chill within his heart pressuring him to give in and freezing the distant roaring of hellfire and the tiny spark of conscience that told him that making a deal with a demon was wrong, that anything Bill wanted was wrong.

Saying that maybe the drowning voice that once roared that this proposition is bad was wrong.

But there was that light at the end of the tunnel again as Bill circled back in front of Dipper's vision, blocking his sister and his sacrifice with an outstretched hand and a damned salvation.

"I meant it when I said I planned all of this just for you, kid." His voice, although as grating and demonic as ever, was different than Dipper had ever heard before. The word softer first came to mind, and while nothing Bill said could ever lose his mischievous quality, it lack some of its normal malicious undertones. "I like you, Pine Tree, and it'd be a shame to watch you burn.

"Just as it'd be a shame to watch Shooting Star burn out, just because you prioritized two murderers' lives over hers."

The howling stopped. It had died down before, dimmed, but Dipper hadn't even realized how quiet silence was until the whole world seemed to freeze besides the soft floating of Bill's passive form.

There was a soft scratching, the sound of a clawed paw ripping through well-worn carpet.

"Oh well, good deal for me either way. I get to drag two souls to Hell for the price of one!"

And suddenly the force holding Dipper was broken. The exhaustion still remained, and the movement was pitiful, barely more than an inch, but Dipper curled his right fist, raised it just off the floor, and extended his hand.

"Fine. But Mabel stays out of it. Protected from you, from Hell, from everyone else! She stays safe, or I'll stop doing whatever spying it is you want me to do for you. Even if it means diving into Hell myself."

Bill's hand was there, bare and static and numb, sending pins and needles down Dipper's palm where they met, as if his hand had fallen asleep. Then came the flame, the fire that had got him into this mess and would pull him out, the one that no one survived and the very reason Dipper did. Bill didn't pull back this time, and uninterrupted the hellfire burned its way up his arm and across his entire body, disappearing as soon as it came without a trace. It had claimed Dipper once before, and recognized the boy as its own, but it wouldn't brand him until the time came.

After all, its biggest advantage in the boy was the element of surprise.

The burst of energy was like a cool caress, and for some reason the burst of light didn't blind Dipper's eyes as much as make them heavy. He could feel the presence lodging in his birthmark and his left eye, making his head fuzzy and his eyelids droopy with oncoming sleep. The tension in his nerves and muscles was now gone and without it there was nothing keeping Pine Tree from collapsing the last few inches onto his bedroom floor.

"Sweet dreams, Pine Tree. And remember to keep an eye on the Winchesters, just as I've been keeping an eye on you."

The dreamscape melted away, the gray seemingly evaporating into the air piece-by-piece, as one eye faded to blackness and the other brightened to color, each equally deep in a dream.

* * *

It was disorienting, at first, looking onto the scene below him from an outside view. He could clearly see his mangled body sleeping on the floor, surrounded by a half-ring of black dust and tangled in ripped sheets. He could see his sister rising from her prone position, wiping blood off of her face while immediately turning to him, running to his side and shaking his shoulders before looking over her shoulder and shouting something to the two Winchesters behind her, the taller equally bloody.

He couldn't even feel her hand.

The sound was fading in and out, and if he focused really hard he could concentrate enough to make out the conversation, but something told him this would get easier with practice. They were saying something about possibly returning and going somewhere safe, and telling Mabel to get everything both twins would need packed. The two men talked to themselves as she emotionlessly went about the room, and while Dipper wanted more than anything to focus on his sister and what he could do to keep her from acting so dead as she gathered the bare necessities, leaving artwork and sweaters and scrapbooks behind, Dipper found his hearing and other senses trapped between the two murderers, as if he wouldn't be aware at all if they weren't in the room.

The next time he bothered to focus Mabel was holding her packed art bag, now stuffed with a couple days' worth of clothing, and Dipper's favorite duffle with what he could assume was his travel gear. The older Winchester patted her on the shoulder as he walked by, grabbing the duffle out of her lifeless grip as she made her way over to Dipper's body. She hefted the backpack on her back and bent down to hold her brother but the taller Winchester beat her to it, easily picking up Dipper in his arms and making his way towards the apartment door. They made their way down the three flights of stairs as silent as a funeral procession, Mabel not even bothering to lock the door she had busted earlier in her haste.

Sam Winchester waited as Mabel slid into the backseat of the car, an old black Chevrolet, before passing Dipper onto her lap, the girl's grip quickly tightening as she hugged his sleeping form. A couple of door slams later and the car was off, the formless psychic sense of Dipper travelling with them.

Mabel hadn't looked back. She hadn't given a thought or glance to the apartment, the home, the life that the twins had left behind them. It wasn't like they had any roots besides each other. Even though neither would have imagined their ties to the world being cut in this way, when they graduated college and entered into a world of distance and individuality they had decided that everything was expendable in comparison to each other. They were twins, after all.

She didn't even glance at the road in front of her, the strangers taking them to whatever new place they would never be able to call home. She only looked at her brothers sleeping form and carded her finger through his hair. Half-formed rings of tears lined her eyes, her mask cracking for only the second time in the seeming eternity since the fight.

Dipper couldn't interact with the world; couldn't move, couldn't speak, couldn't smell or taste or do anything besides see and hear. But the boy never thought about it. It was as if his ghostly state was just a realistic dream: one where there's no question about what's happening until after waking up, and even then only a foreboding sense that's too distant to pinpoint. Dipper, however, had a feeling that he would recall every detail of this dream. In fact, he had a feeling he would remember every single one of these vision-like nightmares from now on.

But through the haze, the numb shadow that made up this comforting void of nonexistence, there was one sensation that shone through as bright as Bill had when making the deal. Dipper had seen (eyes only for his sister despite the one sense that followed the Winchesters wherever they went) Mabel stopping as she followed Sam out of the room, her eyes breaking that straight, dead stare they had ever since Dean pulled her from Dipper's side. She glanced down to her right, glare full of rage and hate and _everything that wasn't Mabel_ as her emotional composition shattered and the shrapnel fired at the innocently bound book sitting stainless on the floor. With all the force she could muster, she slammed her foot into the polished golden seal on the cover, grinding against it the blood and ash and goofer dust that stained her shoes just as it had everything else in their lives strewn about the floor.

Mabel had purposefully left behind the book that was behind her brother's damnation. Venomously, if it was possible to commit an inaction in such a manner.

So then why could Dipper, through all of the dimensions separating him soul from his self, feel the familiar weight of the leather-bound Journal resting in his inside pocket?


End file.
